from the conferences organized by TANGER Ltd.
The fracture initiation and propagation was studied in a novel in-situ Ti-44.5Al-8Nb-4.8C-0.8Mo-0.1B (at%) composite reinforced with carbide particles. The composite was prepared by vacuum induction melting in graphite crucibles and precise casting into graphite mould. The as-cast samples were subjected to hot isostatic pressing and stabilisation annealing. The phase composition of the test specimens was characterised by X-ray diffraction analysis and transmission electron microscopy. The fracture of the composite was studied by scanning electron microscopy (SEM) and SEM in backscattered mode (BSEM). The coarse primary carbide particles are found to be effective obstacles to propagation of cracks initiated in the TiAl matrix during room-temperature three point bending test. The propagation of fracture in the in-situ composite includes crack arrest by carbide particles, crack deflection, delamination on the matrix-carbide interfaces and extraction of some carbide reinforcements from the TiAl matrix.
Keywords: TiAl, carbide particles, composites, three-point bending test, fracture behavior© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.